1. Field of the Invention
This invention pertains generally to retainers or carrier frames for elastomeric electrical connectors. Examples of elastomeric electrical connectors which can be advantageously used in combination with the retainer of this invention are to be found in U.S. Pat. No. 4,003,621, U.S. Pat. No. 3,998,512 and particularly useful are the layered elastomeric electrical connector elements sold under the trademark ZEBRA by Technical Wire Products, Inc.
2. Description of the Prior Art
In recent years, particularly with the substantial reduction in physical dimensions of electronic components such as alpha-numeric displays, integrated circuits, and the like, the use of electrical connectors employing stamped metal contacts have begun to give way to a new class of electrical connectors employing electrically conductive elements which are not wholly metallic. Some such connectors employ electrical conductors which are themselves merely elastomers loaded with electrically conductive materials. Examples of such connectors are to be found in U.S. Pat. Nos. 3,885,173; 3,861,135; 3,648,002; and published Japanese Patent application Sho 49-765 and Sho 47-25523. Other such connectors employ extemely small and substantially linear metal conductors maintained in an array insulated from each other by a single body of elastomer. Examples of such connectors are to be found in U.S. Pat. Nos. 3,795,037; 3,795,884; 3,862,790 and 4,003,621.
These electrical connectors to a lesser or greater degree, employ elastomers as a substantial portion of the conductor-supporting matrix and may be termed generally as elastomeric electrical connectors. Since their advent, the elastomeric electrical connector has enjoyed a mixed reputation. While the connectors have permitted an ease of disassembly and reassembly not achievable through the use of conductive cements, reliability has often been lacking due to problems directly associated with contact potentials developing between the connector itself and the electrically conductive areas sought to be connected. It has usually been assumed that to overcome such problems, one merely increases the contacting area of the elastomeric connector, thereby affording a greater probability of eliminating this undesirable contact potential. This results in yet additional problems related to surface smoothness and linearity of the connector as well as durometer of the elastomers employed since an increase in contact area results in a corresponding increase in total force required to connect the components.
Particularly in connectors using the layered elastomer technique such as is illustrated in U.S. Pat. No. 3,885,173, it has been the general practice in the past to form a self-supporting layered elastomeric strip or ribbon which connects a number of mating electrically conductive areas. In order that the strip or ribbon be self-supporting, the width of the elastomeric strip or ribbon was usually equal to or greater than the dimension of separation between the two sets of electrically conductive areas sought to be connected. Since the total force which could be applied to many electrical components is rather restricted due to the materials used in their construction, the contact pressure between the elastomeric connector and the electrically conductive areas sought to be connected is rather low.
An increase in reliability of elastomeric electrical connectors could be achieved by increasing this contact pressure between the elastomeric electrical connector and the electrically conductive areas sought to be connected by simply reducing the contact area. A reduction in contact area could only be achieved by a substantial reduction in width of the connector while maintaining the same separation between the sets of contact areas. As a result, the elastomeric electrical connector could no longer be self-supporting and some means for supporting the elastomeric connector was necessary. One such support means is to be found in U.S. Pat. No. 3,998,512, which discloses simply a relatively rigid plastic support strip which supports an elastomeric connector having a very small width dimension, the support strip permitting the necessary compression of the elastomeric connector only through a very minor portion of the connector.
Additional examples of the prior art are to be found in U.S. Pat. Nos. 3,858,958; 3,760,330; 3,551,750; 3,542,939; and 3,509,296.